Ignoring all airline rules, would you be able to use a cell phone at
30,000 feet, traveling at 500mph. A yes or no would be cool, also
reasons please.I think that at 8 miles/ min. the cells would not have
time to log on and hand over, and confusion would result. Also there
is the issue of handset power and screening from the aircraft. All
thoughts appreciated. Thanks.

Greetings 250959,
I'd go for the 'no'. Based on what I've found on the net, you may not
be able to use a cell phone at high altitude, since such phones are
meant to be used on the ground and at a lower speed than an
airplane's. If you are able to make a call anyway, the cellular
network would be hard pressed to keep up with the rapid change in your
signal. And your cell phone battery would be drained faster to try to
keep up the signal. But if you're high enough, the signal won't reach
you at all.

Also note that the agency concerned about cellphone use on airplanes
is the FCC (Federal Communications Commission), not the FAA (Federal
Aviation Administration). The idea that cellphones can ruin plane
avionics is not proven. But it's better to play safe.


Sources:
Gizmodo : On cellphones in airplanes
http://gizmodo.net/archives/001900.php

A person though described using a cellphone on a private plane...
which doesn't go as high or as fast as a commercial airplane anyway:
Airplanes and cellular phones (George Goble)
http://yarchive.net/phone/airplane_cellular.html

This page shows how cellphones can become useless at high altitudes.
It also discusses the myth that cellphone calls were made from the
hijacked 9/11 planes:
Media Release - Overcoming 9/11 Myths with Science
http://feralnews.com/issues/911/dewdney/media_release_030304.html

Here'a another page on the above experiment:
'Project Achilles' - Final Report and Summary of Findings - by A. K.
Dewdney - 19th April 2003
http://www.physics911.org/911/index.php/docs/15

Cell Phone Experiments in Airliners - By Germar Rudolf, July 2003
http://www.physics911.org/911/index.php/docs/6

Message from CCTec.com - Re: Operations: where are you going to sit?
http://www.cctec.com/maillists/nanog/historical/0012/msg00092.html

In case you want something on the cellphone/avionics issue:
Cellphones Cannot Interfere with Avionics
http://www.scn.org/~bk269/itssafe.html

Here's an article about Virgin Atlantic setting up a system to allow
calls in flight, though not using the cellphone the passenger owns.
It's probably in use already:
Geek.com Geek News - Cellphones in the sky
http://www.geek.com/news/geeknews/q22000/gee2000706001812.htm

Google Search string: 
cellphones airplanes/airplane
cellphone high altitude

I hope this has been a most helpful answer. If you need anything else,
or have a problem with the answer, do please post a Request for
Clarification and I shall respond as soon as I can. Thank you.

---

Clarification of Answer by techtor-ga on 01 Sep 2003 01:05 PDT

Apologies for misidentifying you, Guitarman2000, I copied the wrong
part of the headings above.

Wow, what a quick response. Many thanks. If I could I would rate you
10 stars but you will have to be content with 5 and a $5 tip. It seems
that a lot of people are muddying the water on this issue. Wonder why?
Thanks again.

With all due respect, I believe the official answer is wrong. 

The following pages all suggest it is possible:
http://www.cctec.com/maillists/nanog/historical/0012/msg00093.html
http://www.washingtonpost.com/ac2/wp-dyn/A14290-2003Jun19?language=printer
http://www.techdirt.com/articles/20030428/1645207_F.shtml
http://www.textually.org/textually/archives/cat_cell_phones_while_drivingflying.htm

Search term: ://www.google.com/search?q=%22cell+phone%22+airplane+high+altitude

Note that the sources given in the official answer come from someone
who is trying to prove a bizarre conspiracy theory regarding 9/11, and
if cell phones could indeed be used in planes it would debunk his
theory.

This previous GA answer on the subject may be of interest to you:

http://answers.google.com/answers/main?cmd=threadview&id=173057

The problem of using the a cell phone from an airplane is not
neccessarily hight but the speed.

GSM cell phones are usually designed to cope with maximum speed of
around 250km/h. The speed is important because the demodulation
algorithm needs to estimate the phase/frequency offset of the
incomming signal and at higher speeds this gets increasingly difficult
(doppler effect).

Important for the doppler effect is not the absolute speed but the
relative speed of the cell phone to the base station. If the plane
flies directly towards or away from the base station than the cell
phone is probably out of luck. If the plane flies perpendicular to the
base station than the doppler frequency is actually zero.

So in cases where the relative speed of the plane and the base station
are within 250km/h things should work.

The maximum distance a GSM cell phone can be from a base station is
35km so this  more than the normal cruising altitude of a plane. So
this should not be a problem
http://www.eecg.toronto.edu/~nazizi/gsm/

Another problem is the the cell phone will "see" many more base
stations than under normal conditions and that can make it difficult
for the base stations to decide which one should link to the phone.

To sum it up under the right conditions it is possible to use the
phone from a plane but don't count on a stable connection.

Many thanks for the high rating and the tip. But you could take the
other comments here into consideration.